1. Field of the Invention
This invention relates to a device for separating slag from molten bath to be discharged from a container, for example, a converter, ladle or the like.
2. Description of the Prior Art
During discharging molten bath from a container, for example, a converter, ladle or the like for enclosing molten metals or alloys and slag floating on and covering the free surface of the molten bath, and, particularly, at the end of the discharging, the slag is often mixed into the molten bath. In general, it is difficult to prevent the slag from mixing into the molten bath.
That is, in the converter, for example, when the discharging of the molten steel approaches to its end, a flow of molten steel is biased toward the edge of a receiving ladle. Under such condition, if a flow of slag is detected in the receiving ladle, the converter is returned to its original vertical position and the slag is removed out of the receiving ladle. In such operation, the mixing of the slag into the molten steel is also unavoidable.
It has also been proposed to use a refractory spherical body having a specific gravity which is the intermediate between a specific gravity of molten steel and that of slag and float it in the molten steel bath and cause it to accompany the flow of molten steel at the end of discharging the molten steel and clog a molten steel discharge hole. But, the use of such measure is not reliable in practice and ensures no desirous complete closure of the molten steel discharge hole.
In the course of discharging the molten steel from the converter, the converter may be returned to its original vertical position to retain the molten steel in the converter or the molten steel may be discharged from a ladle with the aid of a stopper rod or sliding nozzle so as to remain the molten steel in the ladle. But, the use of such measures provides a material decrease in yield.
In addition, the slag mixed into the molten bath as described above functions to decrease the yield of alloys or iron alloys to be added to the molten bath during its discharge and damage the refractory material of the ladle. Moreover, in the case of manufacturing an ingot, the slag mixed into the molten bath considerably deteriorates the quality of the steel ingot.